Advanced Dolphin diving

[NIXERONIUS]

Looking for info/tables for diving the dolphin in methods other than the manufacturer recommends. I am interested in using my Dolphin to dive to possibly 200'. I think it would be possible to use the 32% orifice with a Trimix blend (say 18/44) and safely dive much deeper/longer. A travel mix would probably be necessary, but this could be factor in to a bailout/deco gas supply bottle. Is there anybody with experience with this type of diving? Can you provide tables/advice?

 

[landfish]

i cant tell you about using trimix but i have use the dolphin to 150
i use a 65 steal tank instead of the drager tank with a h valve one for dreager other for oc bail out,at 13 tank for bail out and suit inflator,the 40 al deco botte i have oc set up with a hp line going from the hp port to the drager hp port and i deco threw the dolphin as well which turns that deco bottle into a 2 hour + bottle.
all the calculation are in the tdi manual for air/nitrox
i have done long bottom times and have come up with over 1800 pds of gas left in my bottom mix
i dont get the benifit of a ccr as far as getting the optimum mix but i can do long bottom times with plenty of gas left

 

[deepblueh2o]

What is the flow rate of the 32% orifice? Wasn't out when I used a regulation Dolphin. I used the 60% orifice (flow rate at 5.5 lpm) and dropped the mix to 32 or 36% nitrox depending on depth (couldn't breathe the loop at the surface). What works for you will depend on your metabalizm. I may have the tables that were used for other blends on the 60% orifice. If still interested email me and we can work out faxing them to you. 3 or 4 pages I think. Once you hit deco you will need a big OC bailout. This setup worked fine for me at 150'.

 

[nitr0x]

The 32% jet adds at 17.3 liters per minute.

I regularly dive the dolphin to 150 feet. I use 38% in the bottle and run the 60% jet. This is adding nitrox into the bag at approx 5.7 liters per minute. On the bottom I metabolise at just under 1 liter o2 per minute which gives me a bag mix of about 27%. I know this because I have sensor inside the breathing bag connected to a VR3 computer.

 

[padiscubapro]

Looking for info/tables for diving the dolphin in methods other than the manufacturer recommends. I am interested in using my Dolphin to dive to possibly 200'. I think it would be possible to use the 32% orifice with a Trimix blend (say 18/44) and safely dive much deeper/longer. A travel mix would probably be necessary, but this could be factor in to a bailout/deco gas supply bottle. Is there anybody with experience with this type of diving? Can you provide tables/advice?

Besides the potential problem of not being able tobreath the mix shallow, Helium based mixes have a much lower density.. even though you may be measuring a flow rate as 17lpm it DEFINATELY is not what you are reading.. for every combination of trimix you have to scale the flow rate accordingly..

If you do your research MOST of the divers who use the Dolphin beyond its recommended depths have converted them to CCRs. This is a serious change and should only be attempted by those with the right attitde, training and experience.

I do know of people who have used CCR dolphins to 300 fsw. ANDI used to have a class for an EXPERIMENTAL dolphin RB that was taught in Germany by 2 drager employees who were ANDI ITs. This was a factory designed unit called the Dolphin 80 which had changes allowing use at a greater depth (80m) . The project was canned by Drager.

 

[heliox]

I do know of people who have used CCR dolphins to 300 fsw. ANDI used to have a class for an EXPERIMENTAL dolphin RB that was taught in Germany by 2 drager employees who were ANDI ITs. This was a factory designed unit called the Dolphin 80 which had changes allowing use at a greater depth (80m) . The project was canned by Drager.

I have known a dolphin SCR to be dived at 70+ meters. It can be done however as helium is a lower desity gas it flowes through the orifice at a faster rate than O2 therefore to get the correct amount of both gases going through you will have to use 2 jets one for He the other for O2 or combine the 2 and vary the mix. Saying all this you should always check your mix being delivered using both a O2 analyser and Helium analyser.

 

[deepblueh2o]

I agree with padiscubapro. I later converted a daeger ray to CCR, much better way to go for me. That 32% jet is really kicking out the gas. BIG bottles.